Key



Nov. 14, 1961 w. F. STACKHOUSE KEY Filed Aug. 24, 1959 3,008,322 KEY Filed Aug. 24, 1959, Ser. No. 835,745 1 Claim. (Ci. 70-395) This invention relates to locks of the type employing a plurality of locking plungers normally held in looking position and adapted to be forced to the released position by the insertion of a key having a corresponding number of lands of a height to perform the releasing operation, and the invention relates particularly to a lock of the nature shown in Patents 2,298,697 and 2,298,698 and to an improved key therefor.

The lock described in said patents is employed in public checking cabinets and attempts at key duplication and other abuses cause considerable trouble and require constant vigilence and improvement in equipment to combat such factors. All possible effort is made to produce equipment as near tamper-proof as possible and a primary object of the invention resides in the production of an improved key of the above patented nature that will aid substantially in combating these difficulties.

These and other features of the invention will be best understood and appreciated from the following description of a preferred embodiment thereof selected for purposes of illustration and shown in the accompanying drawings in which:

FIG. 1 is a front end elevation of a lock employing the improved key embodying my invention,

FIG. 2 is a side elevation of the lock mounted in a supporting structure,

FIG. 3 is a sectional view taken on line 33 of FIG. 1,

FIG. 4 is a side elevation of the key,

FIG. 5 is a sectional view through the key on line 5-5 of FIG. 4, and

FIG. 6 is a sectional view taken on line 6-6 of FIG. 3.

The lock shown in the accompanying drawing embodies an outer member 19 having an axial bore therethrough and within which is rotatably mounted an inner member 12. The outer member is the fixed unit and is mounted non-rotatably within a structure 14 supporting the lock, this member having a laterally extending portion 16 fitting within a corresponding recess in the structure 14 and preventing rotation of the member about the axis of the member 12.

The inner member 12 is slotted at 18 to receive the shank portion 213 of a key having a finger gripping base 22, one edge of the key shank being notched at 24 to provide lands for cooperating with radially extending tumbler releasing pins shown in said patents. The outer member 10 together with a portion 25' on one end having oppositely disposed shoulders 26 is provided with a plurality of bores 28 therethrough disposed about and parallel with the rotary axis of the inner member 12 and locking plungers 30 are mounted in these bores. A plate 32 secured to the rear end of the member 12 by screws 34 and overlapping the structure 14 serves to hold the member 10 within the structure between the plate and the shoulders 26 and the member 12 within the member 10 between the plate and a collar 36 on and fixed to the member 12.

The collar 36 is provided with bores 38 therein adapted to receive the plungers 30 when the bores 38 are in alignment with the bores 28, springs 40 being provided in the bores 28 for forcing the plungers forwardly into the bores dtates Patent 9 38. A plurality of plunger releasing pins 42 is provided Patented Nov. 14, 1961 "ice in the bores 38 and the springs 40 normally force the plungers and pins forwardly to contact the pins against an annular shoulder 44 integral with the forward end of the member 12. When the plungers are in this position they extend into both bores 28 and 38 and serve to lock the member 12 against rotation within the member 10.

The key shown in FIGS. 4 and 5 includes a cylindrical barrel 46 rigidly mounted coaxially thereon 'at the junction of the key portions 2% and 22. The barrel is open at its forward end and its closed rear end 45 is slotted to receive the shank of the key therethrough, and the barrel is of an inside and outside diameter to fit over the outer end of the member 12 and Within a cylindrical ferrule 48 on and fixed to the collar 36, all as illustrated in FIG. 3. The forward end of the barrel is recessed to provide a plurality of lands 50 for cooperating with the pins 42, the recesses and lands being spaced about the central axis of the'key and disposed adjacent to and Wholly within the unbroken cylindrical contour of the barrel. The lands are of such respective depths that the locking plungers 30 are forced to the flush and released positions when the barrel is forced inwardly into contact with the collar 36, as illustrated in FIG. 3. As will be understood, the pins 42 are of different lengths and the lands are of different and such corresponding depths as to serve the function described.

As heretofore stated, my novel key is employed in public checking cabinets wherein the keys are subjected to considerable abuse, including attempts to duplicate the keys, and a primary object of the invention is to provide a key that will forestall such abuses and render key duplication extremely difficult if not impossible. Placing of the lands 5d wholly within the unbroken cylindrical contour of the key barrel as renders the key much more difficult to duplicate since the land depths and contours which must be gauged and duplicated are inaccessibly located wholly within the barrel. Locating the lands 50 within the collar also permits a thicker and stronger collar and a stronger joint between the key blade and collar. Also the rear margin 52 of the blade is unbroken throughout its length, thereby better protecting the keyways with consequent savings in maintenance and replacement expense. The novel construction furthermore provides a key much more pleasing in appearance and one in which the lands and pin receiving grooves are wholly protected within the barrel. The fully closed end 45 of the barrel which is slotted to receive the key furthermore aids in producing a stronger key.

Having thus disclosed my invention what -I claim as new and desire to secure by Letters Patent is:

A key comprising a finger gripping base, a shank carried thereby and extending outwardly therefrom for insertion into the key slot of a cylindrical lock member, and a cylindrical barrel coaxial with the shank and fixed thereto adjacent to its junction with the finger gripping base, the cylindrical barrel being open at its forward end to receive said cylindrical lock member thereinto and having a plurality of forwardly facing lands located wholly within the open forward end of said cylindrical barrel and spaced about the shank adjacent to the cylindrical lock member for engaging lock plunger releasing pins disposed about said cylindrical lock member, and the outside contour of said cylindrical barrel being smooth.

Hofmann Oct. 13, 1942 Hofmann Oct. 13, 1942 

